No service and bad attitude

Yesterday, I went into your the brooklyn apple store to purchase a voucher. Firstly the assistant manager asked what I needed after waiting for 15 minutes and then told me he could not assist me as he is not allowed to take cash, he will get one of the assistants to assist me. After being tossed between three assistants who gave me the same excuse I left without getting what I needed. I am disgruntled because I wasted 30 minutes of my time for no service and no voucher which I went there for in the first place.